make ruby-version file to work with rbenv
make ruby-version file to work with rbenv

ramen-dev/moped,drobune/moped,wandenberg/moped,mongoid/moped,fcruxen/moped,johnnytomcat/moped,aijanai/moped,crashlytics/moped,jonhyman/moped,agis-/moped,newsdev/moped,sferik/moped